Fixed bug in VirtualByteString: nil should be a valid VBS.
Fixed ByteString::printReprToStream().
Added the globalization mechanism.
Added the serialization/decycling mechanism.
Serialization of basic data types.
Fixed bug in I/O reading operations.
Added builtins to register new system properties from Oz.

This is mostly useful for properties created by Init and its
parts.
Added output of stacktrace on uncaught exception.
Fixed broken support for BURL.open, used by Open.file with URL.
Added a builtin OS.bootURLLoad.
Added builtins IsArity and GetStructuralBehavior.
Reconciled the pickle and boot-pickle formats.
Added support for the remaining types in bootUnpickle().
Fixed: the needed flag was not GRed in VariableBase.
Added a builtin Record.adjoinAtIfHasFeature.

This is partial work of Record.adjoinAt that succeeds if the
original record already has the feature to adjoin. In this case,
a fast copy is done in C++. Otherwise, the function does not
succeed and AdjoinAt should fallback on a slower implementation.

Eventually, this will be replaced by a complete Record.adjoinAt
as a builtin. But we need this partial implementation to be fast
right now so that PEG.oz is not too slow.
BoostBasedVM sets up a default boot loader.
Allocate 1 GB because we need this to compile Base.oz.
Fixed bug in IsFuture and Value.status for ReadOnlyVariables.
Added some rudimentary dump() methods for threads.
Fixed a bug that could create cyclic References.

E.g. when trying to unify A and B whilst both refer to the same
store node.